Art of double-tonguing boards



UNITED STATES PATENT OFFICE.

SAMUEL J. SHIMER, OF MILTON, PENNSYLVANIA.

ART OF DOUBLE-TONGUING BOARDS.

SPECIFICATION forming part of Letters Patent No. 367,675, dated August 2, 1887.

Application filed November 12, 1886. Serial No. 218,694. (No model.)

To all whom it may concern.-

Be it known that I, SAMUEL J. SIIIMER, a citizen of the United States of America, residing at Milton, in the county of Northuu1- berland and State of Pennsylvania, have in vented a new and useful Improvement in the Art of Double-Tonguing Boards, of which the following is a specification.

My invention has relation to improvements in cutting the double tongue on a board, or two tongues in the face of a board, for 1natching grooves in instances where the stuff to be matched is made from a single board having the grooves made in opposite edges and the tongues cut in the middle of the board from both faces of the stuff, eventuating in divid ing theboard longitudinally, and forming two matched pieces of flooring or similar stock. As the art existed prior to my invention the tongues were cut in the middle by a single groove in opposite faces of the board, which grooves deepened sharply in the center from both directions, the board being parted on the line of the sharplydeepened part. This method, when the cut is heavy or when the capacity of the cutter is crowded, often tears up the edges, splinters the stuff, and spoils one then cutting the ridge or core out by a cutter shorter than the distance between the outer walls of parallel grooves, as will be hereinafter more fully stated.

Accompanying this specification are illustrations intended to show the steps of the process inwhich my invention consists, and showing the cuts as heretofore made.

In the drawings, Figure 1 shows a transverse section of a board double-tongued by the common method, the second cut being shown in dotted lines. Fig. 2 is a transverse section of a board with first cut as I make it. Fig. 3 is a similar view of the second cut;

often attended with the resultant imperfections I have heretofore stated.

The primary successive steps by which I achieve the objects of my improvements are as follows: I first cut in the face of the board two parallcl'grooves, 3, the outer walls of which form the shoulders of the tongues or edges of the boards, and between these groovesis left standing acore, 4, the face of which I prefer to cut down below the face of the board, say to one-eighth of an inch. The parallel grooves are cut down to the base of the tongue, so that when the core is taken out the tongue is formed on that side. I then from belowcut two other parallel grooves, 5, leaving a central core, 6, stand, as in the upper cut, the parallel grooves in opposite sides being in alignment. The board then has the appearance of that shown in Fig. 3 ol. the drawings. These cuts maybe made with bits on'the snrface'headers arranged to overlap, and provided with points for cutting them; and the surface of the core is out below the surface of the board by the bits being formed to cut deeper at that point. I then,preferably from above,arrange a cutter head to cut out the'core 4, which brings the cut to the condition seen in Fig. 4, and I then from below, with a head carrying cutters edges of the parallel grooves, so that the edges shall not be torn, as in the old operation. The cores may be cut out by cutters arranged in the cutterheads and adjusted to follow the line of the cut, and. as a guide a pressure-bar formed with a projection to travel in the grooves may be arranged across the stuff.

In Fig. 6 I have shown in a diagram one ar- IOO rangement of the feed-rollers and cutteuheads by which my process may be accomplished.

In this figure 7 indicates the power; 8, an idler, and 9 a belt connecting the power to the idler. The numerals 10 designate the feedrollers; 11, the driver-wheel; 12, an idler, and 18 a tightener, A is the board in the machine, and in position to cut the upper and lower grooves, respectively, are the heads 14 15, and to cut the cores out, heads 16 and 17, the belt 9 being arranged to rotate the several cutter-heads. The cutters in this arrangement, or substantially so, may be located and grouped in any machine, the main object being to so group the cutters that grooves may be cut out in advance of the core. W

The improvement in the art of double tonguing boards which I have above described is advantageous, because it is a continuous process, the sequence of steps following each other to completion, as the board is passed but once through the machine. The alignment of the opposite grooves is insured, while the danger of splitting the board in turning it to again pass it through the machine is avoided. By cutting the opposite grooves before the cores or ridges formed thereby are cut out the edges of the board adjacent to the tongues are formed when the board is stiff and rigid, and hence there is less danger of making rough or splintered work than by the old plan of running the stuff through the machine twice.

I am aware a machine for making wooden boxes has long since been made wherein parallel kcrfs are cut by circular saws and the part between the kerfs then removed by a rotary cutter. I make no claim to such a machine or method, as it will be perceived that the board must be turned and the process of cutting repeated,which is the common way of double-tonguing, and eventuates in objectionable and defective w0rk,wl1ich it is the obj cot and end of my method to remove.

Vhat I claim is- 1. The improvement in the art of doubletonguing a board during a single passage through the tonguingV-machine,which consists in cutting parallel grooves in both faces of the board, the lower cutting thereof following in sequence the upper cut thereof, and then cutting out the cores left standing between said grooves consecutively from above and below with cutters shorterlthan the distance between the outer walls of opposite grooves, substantially as described.

2. The improvement in the art of double tonguing a board,which consists in cutting parallel grooves in the one face of the board, then cutting parallel grooves in the opposite face of the board in alignment with the first-made grooves, then cutting the core or ridge out between one set of grooves, and then cutting the other core or ridge out, such sequence of cuts following each other as the board passes continuously through the machine, substantially as described.

In witness whereof I have hereunto set my hand in the presence of two attesting witnesses.

SAMUEL J. SI-IIMER.

Attest:

Gno. S. SHIMER, JOHN A. BECK. 

